Scanning electron microscope (SEM) images of a semiconductor device show that lateral extrusion including whiskers and hillocks of an aluminum layer significantly increases when a thickness of the aluminum layer is larger than 4 microns. Such defects of metal contact layer in semiconductor devices not only lead to low throughput of manufacturing process, but also cause device performance deterioration and long term reliability concerns, especially for power management devices, where the high power handling capability often requires aluminum metal contact layer up to 7 microns. Unfortunately current state-of-art technologies do not have the capability of producing whiskers free thick aluminum films while maintaining high throughput. It is therefore a need to develop new metal compositions and processes to form thick metal contact layers for power semiconductor devices that are comparable to the characteristics of thick aluminum layers.